Defn: The force which a body subjected to the action of a force from another body exerts upon the latter body in the opposite direction. Reaction is always equal and opposite to action, that is to say, the actions of two bodies upon each other are always equal and in opposite directions. Sir I. Newton (3d Law of Motion).
5. (Politics)
Defn: Backward tendency or movement after revolution, reform, or great progress in any direction. The new king had, at the very moment at which his fame and fortune reached the highest point, predicted the coming reaction. Macaulay. Reaction time (Physiol.), in nerve physiology, the interval between the application of a stimulus to an end organ of sense and the reaction or resulting movement; — called also physiological time. — Reaction wheel (Mech.), a water wheel driven by the reaction of water, usually one in which the water, entering it centrally, escapes at its periphery in a direction opposed to that of its motion by orifices at right angles, or inclined, to its radii.
REACTIONARY
Re*ac"tion*a*ry, a.
Defn: Being, causing, or favoring reaction; as, reactionary movements.
REACTIONARY
Re*ac"tion*a*ry, n.; pl. Reactionaries (.
Defn: One who favors reaction, or seeks to undo political progress or revolution.
REACTIONIST
Re*ac"tion*ist, n.
Defn: A reactionary. C. Kingsley.
REACTIVE
Re*act`ive, a. Etym: [Cf. F. réactif.]